Originally Posted by borgy
After having upgraded to 4.2.2... I have the same behaviour ....ram decreased to 1.3...in total before with 4.2.1 was 1.6...something strange, if the extra ram has been allocated for gpu....why with 4.2.1 wasn't like now?...in my opinion...they didn't free up the ram after upgrading..it's just locked...
I don't see notable differences between 4.2.2 and 4.2.1.... So that strange...could it be a bug?
The answer to why the total ram availible has decreased has been solved - Read gzub post.
Called it re-allocated, free'd up or locked, The GPU now has 800mb in 4.2.2 all to its self, where as before it had half that. So in running apps you will only see a total of around 1.2gb.
I have a similar issue as the OP.
Sitting idle its running at around 400-500mb used but can, and often does, spike up to over a gb which causes it to not function correctly (Chrome especially seems to throw a massive wobbler and never stay open). I have nothing different installed than I have on my N7 or S3. I mainly use it for browsing, email. If I check running apps there is nothing else there above what was there when it was idling at around 400-500mb.
I have tried a factory reset and the issue still persists. Next step is to roll back to 4.2.1 to see if I can get the stability back as I didn't have these issues on 4.2.1.